Currently, network and other telecommunications industries are utilizing optic signals of visible and invisible light wavelengths traveling down optical fibers to transfer information from one location with another. However, the switches currently used to redirect information down these optical pathways utilize electric signals instead of optic signal. Therefore, the optic signal from the optical fiber must be converted into an electric signal in order to pass through a switch and then reconverted into a optic signal before continuing its travel down another optical fiber. This switching process severely slows the travel time of information within a fiber optic network and increases the cost of transmitting that information. Therefore, as network and other telecommunications infrastructures rely more heavily upon optical fibers and optical-based technologies, the development and use of optical switches become increasingly important.
As discussed in D. J. Bishop et al., The Rise of Optical Switching, Scientific American, vol. 284(1), pp. 88-94 (2001), several approaches to optical switches are currently being investigated. Among these approaches, there are Micro-Electro-Mechanical Systems (MEMS), waveguide circuits, acousto-optical modulation, “micro-bubble” switches, and liquid crystal based switches. One key performance requirement for an optical switch is its ability to handle an increased number of input-to-output channels for meeting current and future bandwidth demand.
One way to meet this requirement is to increase optical switch density via reduction in optical switch size. While there are many ideas and options for optical switches, there have been few technologies that are able to meet the requirement of reduction in switch size along with demonstrated performance excellence, manufacturing robustness and operation reliability. Many of the existing optical switches are manufactured as discrete components. These components tend to be relatively large in size, expensive (due to extensive manual operations required), and manufactured at a lower yield. For example, acousto-optic modulator type switches, have a typical minimum component size of ˜3 mm. Other approaches, such as MEMS, involve moving parts, which not only limit switching speed, but also raise concerns over reliability and lifetime of such device.
Therefore, there exists a need for optical switches that are small, robust, reliable, and that are simple to manufacture.